In recent years, with the spread of mobile terminals, such as portable computers and tablet terminals, an electronic conference has become to be held in the following manners. Users are allowed to input information regarding the conference by using their own mobile terminals, and the input information is displayed on a common screen. Then, while each of users is looking the information displayed on the common screen, the conference is made to progress.
For example, Japanese Unexamined Patent Publication (JP-A) No, 2007-286780 discloses an electronic conference system which includes a display device; a portable memory device configured to record contents written on an entry surface as image data; a reading device configured to read the image data recorded in the portable memory device; and a display control device configured to incorporate the image data read by the reading device as tag image data into image data to be displayed on the display device and to display the resulting the data on the display device.
In such an electronic conference, users are allowed to edit information displayed on a common screen by performing a remote operation from their respective mobile terminals, whereby the discussion can be made efficiently. However, if two or more users perform remote operations simultaneously for the same information from their respective mobile terminals, the remote operations compete to each other. As a result, a problem arises in that it becomes difficult to judge which information is the newest information. Accordingly, in the electronic conference, there exists a necessity to control operations not to compete to each other.
With regard to a technique to prevent such competition among operations, for example, JP-A No. 2009-064241 discloses a document administering device configured to administer a registration form memorized in a registration form memory device. The document administering device includes a judging section configured to judge whether the registration fat in or a file correlated with the registration form is in the course of editing; and a restricting section configured to prohibit editing for the whole of the registration form or the file correlated with the registration form by other users when the registration form or the file correlated with the registration form is being edited.
The JP-A No. 2009-064241 discloses a technique to prevent competition among operations at the time of editing the registration form or the file correlated with the registration form. Since the form is registered in the state of having been prepared to a certain degree, the editing seldom becomes necessary immediately after the registration. Accordingly, in the case of the registration form and the file, if a certain user is in the course of editing, an editing operation by the other users may be prohibited. Even if an editing right is controlled to be given to the first person who has started editing first, there is no problem.
On the other hand, in the electronic conference, users tend to input coming-up information such as sudden ideas at any time into their own mobile terminals so as to display the information on a common screen. Accordingly, in many cases, the editing becomes necessary immediately after the information has been displayed. For example, since the display pattern of information on the screen of the mobile terminal of each of the users is different from that on the common screen, the transmitting person of the information may desire to change the display size, display color, or display position of the information after having transmitted the information. Further, the administrator of the electronic conference also may desire to change the display size, display color, or display position of the displayed information in order to match it with the other information. Furthermore, if the displayed information is improper, the transmitting person of the information or the administrator of the electronic conference may desire to delete the information.
In such a case, as with the JP-A No. 2009-064241, if an editing right is made to be given to the first person who has started editing first, a person (the transmitting person of the information and the administrator) who is intrinsically to be permitted to perform editing becomes unable to perform the editing. Accordingly, there has been a problem that information cannot be shared in an appropriate state. The present invention seeks to solve the problem.